Heather Mills's former nanny lost her claim for sexual discrimination and constructive dismissal today.

Sara Trumble, who was paid £260 a week by Mills, claimed the charity campaigner and former model reduced her to tears with the demands she placed on her, and forced her to work long hours without any extra pay.

The 26-year-old nanny began looking after Beatrice, Mills's daughter with Sir Paul McCartney, in April 2004, when the couple were still together. She told Ashford employment tribunal, in Kent, that she handed in her notice in September 2008 after she was relegated to domestic duties after returning from maternity leave.

At a three-day hearing that began in March she claimed compensation for sex and maternity discrimination. The tribunal judge, Steven Vowles, reserved his judgment until today, when he dismissed the claims.

A spokeswoman for Mills read out a statement in which the former model said she was "delighted" by the result. "Heather is delighted with the decision of the employment tribunal that has dismissed all of Sara Trumble's claims," she said.

"Heather was always a very fair and generous employer to Sara and is very pleased that this has been confirmed by Judge Vowles and the tribunal members unanimously."

Mills wept while giving evidence to the tribunal. She said she had treated Trumble "like a daughter" and showered her with gifts during her employment, including a two-seater sports car. She described how she had met Trumble when she gave her beauty treatments at a health club near McCartney's estate in Rye, East Sussex, and took her on as a nanny to help her better herself.

Mills pointed out that Trumble had asked her to become godmother to her daughter Lily when she was born in 2007, and suggested that if anything she had been too accommodating to her nanny. The pair were "very close" but their relationship turned sour when she refused to give Trumble £4,000 for breast enlargement surgery in the spring of 2008, according to Mills.

She denied that Trumble had been relegated to carrying out household chores after she returned from maternity leave and said she only arranged new childcare for Beatrice after Trumble handed in her notice.

Mills's PA, Sonya Webb, backed her at the tribunal, describing her boss of 10 years as a "more than fair employer".